The parents of a 13-year-old girl adopted from Ethiopia have been accused of starving and locking the girl outside — resulting in hypothermia that killed her.

Hanna Williams was found dead in her backyard on May 12, naked and wrapped in a sheet. She had been living with her adoptive parents, Larry and Carri Williams, since coming to America from Ethiopia in 2008.

Larry Williams, 47, and Carri Williams, 40, were arrested Thursday in Skagit County and are charged with homicide by abuse. They are being held in lieu of $500,000 bail.

Skagit Count Prosecutor Richard Weyrich told NBC station KING 5 that Hanna Williams’ death ranks right up there among the worst cases he’s ever prosecuted.

Taking a break?

Although she died of hypothermia, there were other contributing causes to her death, including severe malnutrition and chronic gastritis, doctors said.

Child Protective Services said there are reports that Hana had lost a significant amount of weight before her death. And the night she died, she was out in the yard naked on a rainy evening, with temperatures in the low 40s.

Further investigation revealed that Hana had a number of injuries on the night she died, including a large lump on the head, bloody marks and injuries “consistent with disciplinary impacts with a switch,” according to court documents released Friday.

Those same documents describe the hellish life that Hana endured in the months before her death – which included systematic withholding of food, forced times outdoors in the cold or locked in a dark closet, interspersed with regular spankings or beatings with a plumbing tool.

In interviews with the parents and other children in the household, investigators determined that the Williams withheld food from Hana as a punishment for being “rebellious,” court documents say.

In addition, Hana was forced to use an outdoor portable toilet behind the barn instead of the home’s indoor bathroom, and she sometimes was made to take cold showers while naked outdoors under a garden hose, the case file says.

The Williams told investigators that they made Hana use the outdoor toilet because she had hepatitis and they didn’t want any of their other children to become infected with the disease.

Other punishments included locking Hana inside a dark closet for hours or days without food while the parents played the Bible on tape and Christian music for her while she was locked inside, according to court documents.

Hana also was forced to sleep in the barn on some nights or kept outside for hours in the cold without adequate clothing or shoes, court documents say – but she was allowed to wear shoes if there was snow on the ground.

The Williams also confirmed that they used a flexible plumbing tool as a switch to punish Hana and some of the other children in their household.

The children told investigators that Hana sometimes was beaten with a switch for standing more than 12 inches away from where she was told to stand or for speaking without permission.

The Williams’ older biological children were sometimes encouraged to join in administering the punishment by their parents.

A witness told investigators that the Williams got their ideas for the disciplinary measures from a book, “How to Train Up Your Child,” which recommends switchings with a plumbing tool, cold water baths, withholding food and putting children out in cold weather as forms of punishment.

Howard Cooper, a retired pastor who said the Williams and their children sometimes attended worship services at his church, said he had no idea abuse was going on inside the home. […]

On the night of Hana’s death, Carri Williams is accused of sending her out in the cold and rain. She was later found naked, face-down, in the mud, according to court documents. […]

The Williams’ other adopted child, a 10-year-old boy who also was adopted at the same time as Hana, is deaf – and also reportedly showed signs of abuse.

Prosecutors say the first-degree assault accusation against the Williams stems from allegations relating to the boy, who was also from Ethiopia but no relation to Hana.

According to court papers, the Williams also withheld food from the boy at times and switched him regularly – sometimes for not listening to them – even though he was deaf. […]

After Hana’s death, CPS convinced a judge to pull Hana’s eight brothers and sister – ages seven to 17 – from their Sedro-Woolley home. Those children are all now in temporary foster care. The parents have requested a hearing to fight to get their children back.

According to charging documents, Carri and Larry Williams starved Hana for days, put her in a locked closet, shower room and forced her to sleep outside in the barn in the cold. She wasn’t allowed to use the bathroom in the house, instead a porta-potty behind the barn. In addition, Hana was struck daily with a plumbing tool, a tube with a round ball on the end.

“The constant striking and not speaking to her would have different effects on a person,” said Weyrich.

Specifically, last Christmas when Hanna was forced to watch the family celebrate Christmas from outside and only let in when her parents had guests.

All of the William’s biological children and adopted son have been removed from the home. In the documents, a book entitled “To Train a Child Up,” was referenced. Weyrich says it includes punishment techniques the Williams’ mimicked.

There have been other child abuse cases linked to the book across the country.

In February 2010 Kevin and Elizabeth Schatz, from Paradise, California, were arrested in the beating death of one child and the severe beating of another.

After pleading guilty in April this year, Kevin Schatz was sentenced to two life terms for second-degree murder and torture. Elizabeth Schatz was sentenced to 13 years, four months for voluntary manslaughter and infliction of unlawful corporal punishment.

District Attorney Mike Ramsey examined ‘No Greater Joy Ministries’ during the investigation but eventually said he didn’t believe the Pearls could be held criminally liable in connection with the Paradise girl’s death because they had “warned against injury to a child.”